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1.
Chirality ; 32(1): 120-134, 2020 01.
Artigo em Alemão | MEDLINE | ID: mdl-31696979

RESUMO

NaClO3 is achiral in solution. If crystallization is performed under a static set-up, it is recognized that the stochastic nucleation probability results in a racemic mixture of the conglomerate. In this paper, we report a reexamination of the crystallization of NaClO3 from static solution in petri dishes that was conducted over a number of years and is based on the count and analysis of several thousand d- vs. l-NaClO3 crystals. Remarkably, instead of an expected nearly 50/50 coin-tossing situation for the d/l crystal frequency, in most of our experiments a statistically significant bias in favor of d- over l-NaClO3 crystals was found. The experiments also showed that the NaClO3 system was relatively insensitive regarding the intentional addition of a variety of optically active agents. Only in some cases, the persisting d-bias observed in the unseeded experiments slightly increased upon the presence of such additives. Nevertheless, experiments in plastic petri dishes or in presence of fungal spores were able to reverse this bias. A literature survey shows that mainly d-directed non-stochastic behavior in the NaClO3 system has been previously observed in other laboratory settings and by the application of different crystallization techniques. So far, the kind of chiral influence that could be at the origin of the observed bias remains unknown. After the examination of several possible chiral influences of physical, chemical and biological origin, we carefully consider the presence of bio-contaminants as most likely for the cause of this effect.

2.
PLoS One ; 14(7): e0218750, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31260466

RESUMO

This study presents multiwall and bamboo-like carbon nanotubes found in samples from the Allende carbonaceous chondrite using high-resolution transmission electron microscopy (HRTEM). A highly disordered lattice observed in this material suggests the presence of chiral domains in it. Our results also show amorphous and poorly-graphitized carbon, nanodiamonds, and onion-like fullerenes. The presence of multiwall and bamboo-like carbon nanotubes have important implications for hypotheses that explain how a probable source of asymmetry in carbonaceous chondrites might have contributed to the enantiomeric excess in soluble organics under extraterrestrial scenarios. This is the first study proving the existence of carbon nanotubes in carbonaceous chondrites.


Assuntos
Meio Ambiente Extraterreno , Meteoroides , Nanodiamantes/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Fulerenos/química , México , Microscopia Eletrônica de Transmissão , Nanodiamantes/química , Nanotubos de Carbono/química
3.
Math Biosci Eng ; 16(4): 2532-2548, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-31137226

RESUMO

In the last two decades, a group of proteins whose mutations are associated with a disease manifested by episodes of muscle weakness (periodic paralysis), changes in heart rhythm (arrhythmia), and developmental abnormalities has been under constant study. This malady is known as Andersen-Tawil syndrome, with ~60% of cases of this syndrome being caused by 16 mutations in the KCNJ2 gene [UniProt ID: P63252-01-P63252-17]. In this work, we present a computational study designed to obtain a fingerprint of Andersen-Tawil mutated proteins and differentiate them from mutated proteins associated with Brugada syndrome and from functional groups of proteins belonging to APD3, UniProt, and CPPsite databases. We show here that Andersen-Tawil mutated proteins are characterized by specific features that can be used to differentiate, with a high level of certainty (90%), proteins carrying these mutations from similar functional groups, such as mutated proteins associated with Brugada syndrome, and from different functional protein and peptide groups, such as antimicrobial peptides, Cell-Penetrating Peptides, and intrinsically disorder proteins. Therefore, our main results allow us to conjecture that it is possible to identify the group of the Andersen-Tawil mutated proteins by their "PIM profile". Furthermore, when we applied this "fingerprint PIM profile" on the UniProt database, we observed that one protein found in humans [UniProt ID: Q9NZV8], and six of all "reviewed" proteins found in living organisms, possess a very similar PIM profile as the Andersen-Tawil mutated protein group. The bioinformatics "fingerprint" of the Andersen-Tawil mutated proteins was retrieved using the in-house bioinformatics system named Polarity Index Method® and supported-at residues level- by the algorithms for the prediction of intrinsic disorder predisposition, such as PONDR® FIT, PONDR® VLXT, PONDR® VSL2, PONDR® VL3, FoldIndex, IUPred, and TopIDP.


Assuntos
Síndrome de Andersen/genética , Biologia Computacional/métodos , Informática Médica/métodos , Mutação , Algoritmos , Simulação por Computador , Bases de Dados de Proteínas , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Canais de Potássio Corretores do Fluxo de Internalização/genética , Medicina de Precisão
4.
Cell Biochem Biophys ; 76(3): 411-431, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29511990

RESUMO

The number of fatalities and economic losses caused by the Ebola virus infection across the planet culminated in the havoc that occurred between August and November 2014. However, little is known about the molecular protein profile of this devastating virus. This work represents a thorough bioinformatics analysis of the regularities of charge distribution (polar profiles) in two groups of proteins and their functional domains associated with Ebola virus disease: Ebola virus proteins and Human proteins interacting with Ebola virus. Our analysis reveals that a fragment exists in each of these proteins-one named the "functional domain"-with the polar profile similar to the polar profile of the protein that contains it. Each protein is formed by a group of short sub-sequences, where each fragment has a different and distinctive polar profile and where the polar profile between adjacent short sub-sequences changes orderly and gradually to coincide with the polar profile of the whole protein. When using the charge distribution as a metric, it was observed that it effectively discriminates the proteins from their functional domains. As a counterexample, the same test was applied to a set of synthetic proteins built for that purpose, revealing that any of the regularities reported here for the Ebola virus proteins and human proteins interacting with Ebola virus were not present in the synthetic proteins. Our results indicate that the polar profile of each protein studied and its corresponding functional domain are similar. Thus, when building each protein from its functional domai-adding one amino acid at a time and plotting each time its polar profile-it was observed that the resulting graphs can be divided into groups with similar polar profiles.


Assuntos
Doença pelo Vírus Ebola/patologia , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Virais/metabolismo , Biologia Computacional/métodos , Bases de Dados de Proteínas , Ebolavirus/metabolismo , Doença pelo Vírus Ebola/metabolismo , Doença pelo Vírus Ebola/virologia , Humanos , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/metabolismo , Proteínas de Membrana Transportadoras/química , Modelos Teóricos , Proteínas Virais/química
5.
Acta Biochim Pol ; 64(1): 117-122, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28284023

RESUMO

This paper addresses the polar profile of ancient proteins using a comparative study of amino acids found in 25 000 000-year-old shells described in Abelson's work. We simulated the polar profile with a computer platform that represented an evolutionary computational toy model that mimicked the generation of small proteins starting from a pool of monomeric amino acids and that included several dynamic properties, such as self-replication and fragmentation-recombination of the proteins. The simulations were taken up to 15 generations and produced a considerable number of proteins of 25 amino acids in length. The computational model included the amino acids found in the ancient shells, the thermal degradation factor, and the relative abundance of the amino acids observed in the Miller-Urey experimental simulation of the prebiotic amino acid formation. We found that the amino acid polar profiles of the ancient shells and those simulated and extrapolated from the Miller-Urey abundances are coincident.


Assuntos
Aminoácidos/química , Simulação por Computador , Evolução Química , Origem da Vida , Proteínas/química , Exoesqueleto/química , Animais , Modelos Químicos , Paleontologia/métodos , Prebióticos
6.
Science ; 355(6321): 141, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28082555

RESUMO

We detected ribose and related sugars in the organic residues of simulated interstellar ices using multidimensional gas chromatography. Kawai questions the formation of sugar compounds in the ices and suggests that they arise from a classical formose reaction during sample workup for analysis. We disagree with this hypothesis and present additional data to argue that Kawai's criticism does not apply.


Assuntos
Gelo/análise , Ribose , Meio Ambiente Extraterreno , Compostos Orgânicos , Raios Ultravioleta
7.
Acta Biochim Pol ; 64(1): 99-111, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27824362

RESUMO

Preeclampsia, hemorrhage, and infection are the leading causes of maternal death in underdeveloped countries. Since several proteins associated with preeclampsia are known, we conducted a computational study which evaluated the commonness and potential functionality of intrinsic disorder of these proteins and also made an attempt to characterize their origin. The origin of the preeclampsia-related proteins was assessed with a supervised technique, a Polarity Index Method (PIM), which evaluates the electronegativity of proteins based solely on their sequence. The commonness of intrinsic disorder was evaluated using several disorder predictors from the PONDR family, the charge-hydropathy plot (CH-plot) and cumulative distribution function (CDF) analyses, and using the MobiDB web-based tool, whereas potential functionality of intrinsic disorder was studied with the D2P2 resource and ANCHOR predictor of disorder-based binding sites, and the STRING tool was used to build the interactivity networks of the preeclampsia-related proteins. Peculiarities of the PIM-derived polar profile of the group of preeclampsia-related proteins were then compared with profiles of a group of lipoproteins, antimicrobial peptides, angiogenesis-related proteins, and the intrinsically disordered proteins. Our results showed a high graphical correlation between preeclampsia proteins, lipoproteins, and the angiogenesis proteins. We also showed that many preeclampsia-related proteins contain numerous functional disordered regions. Therefore, these bioinformatics results led us to assume that the preeclampsia proteins are highly associated with the lipoproteins group, and that some preeclampsia-related proteins contain significant amounts of functional disorders.


Assuntos
Lipoproteínas/química , Modelos Moleculares , Pré-Eclâmpsia , Conformação Proteica , Proteínas/química , Adulto , Sítios de Ligação , Biologia Computacional , Feminino , Humanos , Lipoproteínas LDL , Neovascularização Fisiológica , Gravidez , Análise de Sequência de Proteína
8.
Acta Biochim Pol ; 64(1): 17-19, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27741325

RESUMO

The behavior of a slight chiral bias in favor of l-amino acids over d-amino acids was studied in an evolutionary mathematical model generating mixed chiral peptide hexamers. The simulations aimed to reproduce a very generalized prebiotic scenario involving a specified couple of amino acid enantiomers and a possible asymmetric amplification through autocatalytic peptide self-replication while forming small multimers of a defined length. Our simplified model allowed the observation of a small ascending but not conclusive tendency in the l-amino acid over the d-amino acid profile for the resulting mixed chiral hexamers in computer simulations of 100 peptide generations. This simulation was carried out by changing the chiral bias from 1% to 3%, in three stages of 15, 50 and 100 generations to observe any alteration that could mean a drastic change in behavior. So far, our simulations lead to the assumption that under the exposure of very slight non-racemic conditions, a significant bias between l- and d-amino acids, as present in our biosphere, was unlikely generated under prebiotic conditions if autocatalytic peptide self-replication was the main or the only driving force of chiral auto-amplification.


Assuntos
Aminoácidos/química , Evolução Química , Modelos Teóricos , Estereoisomerismo , Catálise , Peptídeos/química , Prebióticos
9.
Micromachines (Basel) ; 8(7)2017 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-30400392

RESUMO

Most epidemiological surveillance systems for severe infections with epidemic potential are based on accumulated symptomatic cases in defined geographical areas. Eventually, all cases have to be clinically verified to confirm an outbreak. These patients will present high fever at the early stages of the disease. Here, we introduce a non-invasive low-cost electronic device (bracelet) that measures and reports 24/7, year-round information on the temperature, geographical location, and identification of the subject using the device. The data receiver can be installed in a tower (ground) or a drone (air) in densely populated or remote areas. The prototype was made with low-cost electronic components, and it was tested indoors and outdoors. The prototype shows efficient ground and air connectivity. This electronic device will allow health professionals to monitor the prevalence of fever in a geographical area and to reduce the time span between the presentation of the first cases of a potential outbreak and their medical evaluation by giving an early warning. Field tests of the device, programs, and technical diagrams of the prototype are available as Supplementary Materials.

10.
Micromachines (Basel) ; 8(10)2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30400482

RESUMO

There are a growing number of small children-as well as adults-with mental disabilities (including elderly citizens with Alzheimer's disease or other forms of age-related dementia) that are getting lost in rural and urban areas for various reasons. Establishing their location within the first 72 h is crucial because lost people are exposed to all kinds of adverse conditions and in the case of the elderly, this is further aggravated if prescribed medication is needed. Herein we describe a non-invasive, low-cost electronic device that operates constantly, keeping track of time, the geographical location and the identification of the subject using it. The prototype was made using commercial low-cost electronic components. This electronic device shows high connectivity in open and closed areas and identifies the geographical location of a lost subject. We freely provide the software and technical diagrams of the prototypes.

11.
J Chem Phys ; 144(17): 174701, 2016 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-27155641

RESUMO

Since the early work on Liesegang rings in gels, they have been a reference point for the study of pattern formation in chemical physics. Here we present a variant of the Liesegang experiment in gas phase, where ammonia and hydrochloric acid react within a glass tube producing a precipitate, which deposits along the tube wall producing a spatial pattern. With this apparently simple experiment a wide range of rich phenomenon can be observed due to the presence of convective flows and irregular dynamics reminiscent of turbulent behavior, for which precise measurements are scarce. In this first part of our work, we describe in detail the experimental setup, the method of data acquisition, the image processing, and the procedure used to obtain an intensity profile, which is representative of the amount of precipitate deposited at the tube walls. Special attention is devoted to the techniques rendering a data series reliable for statistical studies and model building, which may contribute to a characterization and understanding of the pattern formation phenomenon under consideration. As a first step in this direction, based on our data, we are able to show that the observed band pattern follows, with slight deviations, the spacing law encountered in common Liesegang rings, despite that the experimental conditions are very different. A further statistical correlation analysis of the data constitutes Paper II of this research.

12.
Acta Biochim Pol ; 63(2): 235-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27059017

RESUMO

The lipoproteins are an important group of cargo proteins known for their unique capability to transport lipids. By applying the Polarity index algorithm, which has a metric that only considers the polar profile of the linear sequences of the lipoprotein group, we obtained an analytical and structural differentiation of all the lipoproteins found in UniProt Database. Also, the functional groups of lipoproteins, and particularly of the set of lipoproteins relevant to atherosclerosis, were analyzed with the same method to reveal their structural preference, and the results of Polarity index analysis were verified by an alternate test, the Cumulative Distribution Function algorithm, applied to the same groups of lipoproteins.


Assuntos
Lipoproteínas/classificação , Algoritmos , Aterosclerose , Biologia Computacional , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipoproteínas/química , Dobramento de Proteína , Elementos Estruturais de Proteínas , Relação Quantitativa Estrutura-Atividade
13.
Acta Biochim Pol ; 63(2): 229-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27059018

RESUMO

Proteins in the post-genome era impose diverse research challenges, the main are the understanding of their structure-function mechanism, and the growing need for new pharmaceutical drugs, particularly antibiotics that help clinicians treat the ever- increasing number of Multidrug-Resistant Organisms (MDROs). Although, there is a wide range of mathematical-computational algorithms to satisfy the demand, among them the Quantitative Structure-Activity Relationship algorithms that have shown better performance using a characteristic training data of the property searched; their performance has stagnated regardless of the number of metrics they evaluate and their complexity. This article reviews the characteristics of these metrics, and the need to reconsider the mathematical structure that expresses them, directing their design to a more comprehensive algebraic structure. It also shows how the main function of a protein can be determined by measuring the polarity of its linear sequence, with a high level of accuracy, and how such exhaustive metric stands as a "fingerprint" that can be applied to scan the protein regions to obtain new pharmaceutical drugs, and thus to establish how the singularities led to the specialization of the protein groups known today.


Assuntos
Proteínas/química , Algoritmos , Animais , Biologia Computacional , Humanos , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Elementos Estruturais de Proteínas , Relação Quantitativa Estrutura-Atividade
14.
Science ; 352(6282): 208-12, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-27124456

RESUMO

Ribose is the central molecular subunit in RNA, but the prebiotic origin of ribose remains unknown. We observed the formation of substantial quantities of ribose and a diversity of structurally related sugar molecules such as arabinose, xylose, and lyxose in the room-temperature organic residues of photo-processed interstellar ice analogs initially composed of H2O, CH3OH, and NH3 Our results suggest that the generation of numerous sugar molecules, including the aldopentose ribose, may be possible from photochemical and thermal treatment of cosmic ices in the late stages of the solar nebula. Our detection of ribose provides plausible insights into the chemical processes that could lead to formation of biologically relevant molecules in suitable planetary environments.


Assuntos
Radiação Cósmica , Gelo , Origem da Vida , RNA/química , Ribose/síntese química , Ácido Acético/química , Amônia/química , Arabinose/síntese química , Meio Ambiente Extraterreno , Meteoroides , Pentoses/síntese química , Processos Fotoquímicos , Raios Ultravioleta , Xilose/síntese química
15.
Sci Rep ; 6: 23402, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-27025405

RESUMO

Liesegang pattern formations are widely spread in nature. In spite of a comparably simple experimental setup under laboratory conditions, a variety of spatio-temporal structures may arise. Presumably because of easier control of the experimental conditions, Liesegang pattern formation was mainly studied in gel systems during more than a century. Here we consider pattern formation in a gas phase, where beautiful but highly complex reaction-diffusion-convection dynamics are uncovered by means of a specific laser technique. A quantitative analysis reveals that two different, apparently independent processes, both highly correlated and synchronized across the extension of the reaction cloud, act on different time scales. Each of them imprints a different structure of salt precipitation at the tube walls.

17.
Gac Med Mex ; 151(3): 313-7, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26089266

RESUMO

INTRODUCTION: In most places all over the world­including our country­services in emergency rooms are oversaturated. This situation frequently forces the continuously arriving ambulances to be redirected to other medical units, delaying the admission of patients moved and thus adversely affecting their physical condition. OBJECTIVE: To introduce an improvement to the Índicede Saturación Modificado computational system, which monitors the degree of saturation of a network of emergency medical services, to include a network of ambulances, enabling in the system: (i) the effective allocation of ambulances to the site of the accident, or severe clinical event, and (ii) the remote booking of beds in the nearest and least saturated emergency room available. MATERIAL AND METHODS: The evaluation and connectivity of the computational improvement to the Índicede Saturación Modificado system was carried out with a computational test verifying these two aspects, using only differences in postal codes, for time measuring. RESULTS: The verification of its sustainability online showed the new Índice de Saturación Modificado y Ambulancias system (ISMA) has a robust structure capable of being adapted to mobile phones, laptops or tablets, and can efficiently administrate: (i) the quantification of excessive demand in the emergency room services of a hospital network, (ii) the allocation of ambulances attending the site of the event or contingency, and (iii) the allocation of ambulances and patients, in the best distance-time conditions, from the site of the accident or clinical event to the nearest and least saturated emergency room service. CONCLUSIONS: This administrative management tool is efficient and simple to use, and it optimally relates independent service networks.


Assuntos
Ambulâncias/organização & administração , Sistemas de Comunicação entre Serviços de Emergência , Serviço Hospitalar de Emergência/organização & administração , Telefone Celular , Computadores de Mão , Humanos , México
18.
Acta Biochim Pol ; 62(2): 191-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26020061

RESUMO

With almost one third of the world population infected, tuberculosis is one of the most devastating diseases worldwide and it is a major threat to any healthcare system. With the mathematical-computational method named "Polarity Index Method", already published by this group, we identified, with high accuracy (70%), proteins related to Mycobacterium tuberculosis bacteria virulence pathway from the Tuberculist Database. The test considered the totality of proteins cataloged in the main domains: fungi, bacteria, and viruses from three databases: Antimicrobial Peptide Database (APD2), Tuberculist Database, Uniprot Database, and four antigens of Mycobacterium tuberculosis: PstS-1, 38-kDa, 19-kDa, and H37Rv ORF. The method described was calibrated with each database to achieve the same performance, showing a high percentage of coincidence in the identification of proteins associated with Mycobacterium tuberculosis bacteria virulence pathway located in the Tuberculist Database, and identifying a polar pattern regardless of the group studied. This method has already been used in the identification of diverse groups of proteins and peptides, showing that it is an effective discriminant. Its metric considers only one physico-chemical property, i.e. polarity.


Assuntos
Proteínas de Bactérias/análise , Proteínas de Bactérias/metabolismo , Biologia Computacional/métodos , Mycobacterium tuberculosis/patogenicidade , Proteômica/métodos , Algoritmos , Sequência de Aminoácidos , Antígenos de Bactérias/análise , Antígenos de Bactérias/metabolismo , Bases de Dados de Proteínas , Dados de Sequência Molecular , Mycobacterium tuberculosis/metabolismo
19.
Acta Biochim Pol ; 62(1): 41-55, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25669158

RESUMO

There is a natural protein form, insoluble and resistant to proteolysis, adopted by many proteins independently of their amino acid sequences via specific misfolding-aggregation process. This dynamic process occurs in parallel with or as an alternative to physiologic folding, generating toxic protein aggregates that are deposited and accumulated in various organs and tissues. These proteinaceous deposits typically represent bundles of ß-sheet-enriched fibrillar species known as the amyloid fibrils that are responsible for serious pathological conditions, including but not limited to neurodegenerative diseases, grouped under the term amyloidoses. The proteins that might adopt this fibrillar conformation are some globular proteins and natively unfolded (or intrinsically disordered) proteins. Our work shows that intrinsically disordered and intrinsically ordered proteins can be reliably identified, discriminated, and differentiated by analyzing their polarity profiles generated using a computational tool known as the polarity index method (Polanco & Samaniego, 2009; Polanco et al., 2012; 2013; 2013a; 2014; 2014a; 2014b; 2014c; 2014d). We also show that proteins expressed in neurons can be differentiated from proteins in these two groups based on their polarity profiles, and also that this computational tool can be used to identify proteins associated with amyloidoses. The efficiency of the proposed method is high (i.e. 70%) as evidenced by the analysis of peptides and proteins in the APD2 database (2012), AVPpred database (2013), and CPPsite database (2013), the set of selective antibacterial peptides from del Rio et al. (2001), the sets of natively unfolded and natively folded proteins from Oldfield et al. (2005), the set of human revised proteins expressed in neurons, and non-human revised proteins expressed in neurons, from the Uniprot database (2014), and also the set of amyloidogenic proteins from the AmyPDB database (2014).


Assuntos
Proteínas Amiloidogênicas/química , Amiloidose/metabolismo , Sequência de Aminoácidos , Proteínas Amiloidogênicas/metabolismo , Animais , Bases de Dados de Proteínas , Humanos , Dados de Sequência Molecular , Neurônios/metabolismo
20.
Proc Natl Acad Sci U S A ; 112(4): 965-70, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25583475

RESUMO

Evolved interstellar ices observed in dense protostellar molecular clouds may arguably be considered as part of precometary materials that will later fall on primitive telluric planets, bringing a wealth of complex organic compounds. In our laboratory, experiments reproducing the photo/thermochemical evolution of these ices are routinely performed. Following previous amino acid identifications in the resulting room temperature organic residues, we have searched for a different family of molecules of potential prebiotic interest. Using multidimensional gas chromatography coupled to time-of-flight mass spectrometry, we have detected 10 aldehydes, including the sugar-related glycolaldehyde and glyceraldehyde--two species considered as key prebiotic intermediates in the first steps toward the synthesis of ribonucleotides in a planetary environment. The presence of ammonia in water and methanol ice mixtures appears essential for the recovery of these aldehydes in the refractory organic residue at room temperature, although these products are free of nitrogen. We finally point out the importance of detecting aldehydes and sugars in extraterrestrial environments, in the gas phase of hot molecular clouds, and, more importantly, in comets and in primitive meteorites that have most probably seeded the Earth with organic material as early as 4.2 billion years ago.

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